Electric switch



Junek, 1933. H, A DQUGLAS 1,912,624

` ELECTRIC swITcH Filed July 1 3, 1932 if za fra/enger drawing,

Patented June 6, 1933 HARRY A. DOUGLAS, l' BBONBON, MICHIGAN mmc SWITCH appunti mea' my is, mail.` semi lo. maca This invention relates to electric switches and more particularly to switches of the socalled toggle type which may be selectively biased to different operative. positions.

The invention is particularly useful whenv embodied in a four-position toggle switch adapted to be mounted on the instrument panel of an automotive vehicle, for example.

Among other objects, the invention aims to prove a switch of thefcharactei' referred to which is simple in construction, and which at the same time will operate with a positive snap action.

My improved switch embodies a minimum of parts and is desirably inexpensive to manufacture, both marked advantages since switches of this type are usually made small and inconspicuous and sell at a relatively low price.

The invention will be more fully exlained in connection with the accompanyin whichigure 1 is a front elevation of my improved switch and mounting therefor;

Figure 2 is a lon 'tudinal section taken on the line 2--2 of igure 1 on a somewhat lar r scale; y

iegure 3 is a cross-section taken on the line 3-3 of Figure 4;

Figure 4 is a longitudinal section taken on the hne 4-4 of igure 1 on a somewhat larger scale similar to Figure 2, but parts being shown in elevation; and

Figure 5 is a perspective view of one of the contact bars inc uded in the structure of the foregoing figures.

The illustrative switch desirably includes the cylindrical metallic casing 1 open at both ends and having the internal shoulder 2. The casing on its cylindrical exterior as at 3 so as to permit the clamping nuts 4 and 5 to be screwed thereon vto clamp the casing to a suitable mountin 6 which may be the instrument panel o an automotive vehicle, for example. f

One end of the casing 1 carries a block of insulation which acts as a closure for that end and alsoas a contact carrier for the electric contactsl of the switch. In this instance,

is advantageously screw-threaded P this .block of insulation is formed of two cruciform separate fiber layers 7 and 8 which ma be appropriately secured to the casing 'as .y four integral prongs 8a formed on the casin and bent over the fiber layers in a well own manner.

The two fiber layers have clamped between theinand thus secured to the casin the metallic contacts 9, 10, 11 and 12, w ich comprise, respectively, the contact bars 13, 14, 15 and 16, each of which terminates on the exterior of the casing in a wire binding means which includes a binding screw 17.

-The contact bars 13, 14, 15 and 16 are received in notches 18 in the margins of the fiber la er 8, are then bent to lie flatly be, tween e laylers 7 and 8 and are then turned to project t rough slots 20 in the layer 7 to terminate inside the casing in the contacts 9, 10, 11, and 12. The contact 12 is desirably somewhat dome-shaped and is disposed centrally of the casing-while the contacts 9, 10 and 11 are agrouped circumferen-l tially about the centr contact 12. A stop 19 formed integrally with the contact 12 and disposed diametrically opposite the contact 10 completes the circle and constitutes the off position of the switch as presently explained.

Pivoted on the dome-shaped contact 12, in this instance loosely, for universal movement thereabout, I have shown the metallic bridge plate 21 which is desirably circular and on one of its faces has a shallow spheroidal depression 22 which receives the dome-shaped contact 12. On its other face the plate 21 has a cup-shape recess 23 which receives the insulating insert 24.

In the illustrative construction the bridge late 21 is held to its pivot on the contact 22 by the metallic operating rod 25, the head 26 of which bears against the insulating insert 24. The operating rod is loosely carried by a bearing shell 27 which closes the open'end 28 of the casin 1. The bearing member 27 has a spheroi al portion such as the hollow hemispherical portion 29 which has a universal bearing within the casing and desirably cooperating with the internal shoulder 2. Axially of t e bearing member 27 the walls of the hemispherical ortion 29 are continued to form a tubular s ank ortion 30.through which the operatin r 2 5 passes. The rod 25 is thus movab e longitudinally in the bearing member 27 and a shoulder 31 on the rod limits movement thereof in the bearing member outwardly of the casing. Interposed between the bearing member 27 and an abutment on the rod witliin the casin in the present case formed by the head 26, have shown resilient means such as the compression coil sprin 32 urging the rod 25 against the bridging plate 21. Since the hemispherical portion 29 of the bearing member 27 is shown hollow, the spring may be received in this hollow port1on and thus conservation of space effected. B manual operation of the guter end 33 of the operatin rod 25, which provides a handle, the hea 26 may be moved to any point within the area of a circle described on the face of the insulating insert 24, the parts being so arranged that said circle is spaced from the metallic portion of the plate 21, so that the rod 25 is always insulated therefrom. So constructed and arranged, the plate 21 may be tilted on the contact 12 and into engagement with one of the circumferentiall disposed contacts to form an electrical bridge between one of these and the central contact 12. Thus the switch may have four operative positions, three on positions of the switch being provided when the plate 21 is tilted to engage the central Contact 12 and one of the contacts 9, 10 and 1l, and the fourth or off position of the switch being provided when the late 21 is tilted to engage the contact 12 an the abutment 19 similar to the contacts 9, 10 and 11, but integral with the contact 12 and therefore discontinuing a circuit therethrough.

In order to conveniently establish these four operative positions of the switch, the margin 34 of the open end 28 of the casing 1 may have four arcuate notches 35 therearound, each of which by receiving the shank 30 of the bearing member 27 determines one of the operative positions as described.

The spring 32 assists in yieldingly retaining the bearing member 27 in engagement with one of these notches, so that the operation of the switch is rendered desirably positive, since when the bearing member is so located, it must be moved out of the notch by manipulation of the rod 25, against the force of the spring 32. Obviously, since the rod 25 is movable longitudinally in the bearing member 27, the spring 32 not only serves to urge the head 26 of the rod against the plate 21, but also serves to urge the bearing member 27 in the opposite direction and into engagement with the inner wall of the casing surroundin the opening 28. Also since the rod 25 1s freely movable longitudinally in the bearing member 27, the

miaou snap action of the switch is enhanced when the rod is swung laterally to tilt the plate 21 as described, the rod beim permitted to move inwardly of the casing. as a unit to compensate for varying distances between the mner end of the shank and head 26 of the rod.

So constructed and arranged the rod 25 provides integrally a handle upon the exterior of the casing and an actuator within the casing, thus effecting simplicity of construction and positive operation.

Having described an embodiment of my invention, I claim:

l. A switch comprising a casing; a bearing member havin bearing relation with the inner wall of ne casing; an operating rod carried by the bearing member, said rod passin through the bearing member and movab e longitudinally therein; an abutment on said rod within the casing; and a spring carried by the rod and interposed between the bearing member and said abutment to urge the rod inwardly of the casing.

2. A switch comprising an open end casing; a bearing member having a spheroidal surface closing the end of the casing and having a universal bearing on the inner wall of the casing; an operating rod carried by the bearing member, said rod passing axially through the bearing member and movable longitudinally therein; a head on said rod within the casing; and a spring carried by the rod and interposed between the bearing member and said wardly of the casing.

3. A switch comprising a metallic casing open at both ends; a bearing member having a spheroidal portion closing one end of the casing and having a universal bearing on the inner wall of the casing; an operatin rod carried by the bearin member, said ro passing axially throu h te bearing member and movable longitu inally therein; a head on said rod within the casing; a coil spring carried by the rod and 'inter sed between the bearing member and saidpliead to urge the rod inwardl of the casing; a closure for the other endy of the casing, said closure carrying a plurality of insulated contacts; and a metallic bridge plate pivoted on one of the contacts and tiltable by said rod into engagement with another contact.

4. A switch comprising a cylindrical cas-A ing havin an open end; a hollow bearing member avin a hemispherical portion bearing upon te inner wall of the casing about said open end; a tubular shank extension of the bearing member arranged centrally of the hernis herical portion and extendin outwardly oi) the casing; an operating r passin snugly through said shank and movable on itudinally therein; a shoulder on the rod limiting movement of head to urge the rod inthe rod outwardly of the shank; a head at the inner end of the rod; and a coil spring carried by the rod and interposed between thelbearing member and the said head, said spring being received within the hollow hemispherical portion of the bearing memr. 5. A switch comprising a metallic casing open at both ends; a bearing member having a spheroidal portion closing one end of the casing and having a universal bearing on the inner wall of the casing; an 0perating rod carried by thebearing member and movable longitudinally therein, saidv rod pgssing axially through the bearing memr; a head on said rod within the casing; a coil spring carried b the rod and interposedA between the bearing member and'said ead to ur the casing, said closure carrying a central contact and a plurality of circumferentially disposed complemental contacts; a metallic plate universall pivoted on the central contact and tiltab e by said rod into engagl- A ment selectively with the circumferentia y disposed contacts.

6. A switch comprising a metallic casingv open at both ends; a bearing vmember hav- -ing al spheroidal portion closing one end of the casing and having a universal bearin on the inner wall of the casing; a metallic operating rod carried by the bearing meminto engagement with another contact, said end of the casing and equally spaced there-r plate ca ng an insulating insert against which the ead of the rod bears.

7. The structure of claim 6 wherein 'the the rod inwardly of the casing; an insulating closure for the other end of closure, said contacts embodying contact bars passing through the closure; one of said contacts terminating within the casing in a dome-shaped contact centrally dis osed and the other contacts being circum erentially disposed about the dome-shaped contact; a metallic brid plate having a central shallow cup portion universally pivoted on the dome-s a-ped contacts and carr ing-an insulating insert on its opposite fyace engageable gy the rod head. f

9. he structure of claim 8 wherein the insulating closure embodies two separable layers of insulating material between which the contact bars are clamped.

10. The structure of claim 8 wherein the insulating closure embodies two separable layers of insulating material between which the contact bars are clamped and wherein the contact bars terminate upon the outside of the casing in wire binding screw means.

In witness whereof, I hereunto subscribe my name.

HARRY A. DOUGLAS.

casing is exteriorly screw threaded and. carries a pair of clamping nuts thereon.

aving a universal bearing on the inner shoulder of the casi-ng; a A

metallic o l ratin rod carried by the bearing mem r an movable longitudinally therein; a head on 'said rod within the cas'- ing; a coil-spring carried by the rod andv inter osed between the bearing member and said ead to urge the rod inwardl of the easing; prongs extending from' t e other about; a cruciform insulatin closure for saidv other end clamped to t e casing by said prongs; metallic contacts carried by thev 

